Thermostatic circuit-closer.



R. L. SHANNON.

THBRMOSTATIG CIRCUIT CLOSER.

APPLIOATION FILED JUNE 7, 191a.

Patented'Apr. 7, 1914. (26 91 Svwwwhov flZ. Sim/272 07a,

COLUMBIA PLANOGRAPH CO.,W/\SH!NGTON, D. c.

UNITED srarns PATENT orrion.

ROBERT L. SHANNON, OF RIPLEY, MISSISSIPPI.

THERMOSTATIC CIRCUIT-CLOSER.

Application filed June 7, 1913.

To all whom it may concern:

Be it known that I, ROBERT L. SHANNON, a citizen of the United States, residing at Ripley, in the county of Tippah and State of Mississippi, have invented new and useful Improvements in Thermostatic Circuit- Closers, of which the following is a specifition.

This invention relates to improvements in thermostatic circuit closers.

In carrying out the present invention, it is my purpose to provide a thermostatic circuit closer which will embrace the desired features of simplicity, efliciency and durability, one which will be reliable and efficient in operation and one which may be manufac tured and installed at a minimum expense,

With the above and other objects in view, the invention consists in the construction, combination and arrangement of parts here inafter set forth in and falling within the scope of the claim.

In the accompanying drawing, Figure 1 is a plan view of a circuit closer constructed in accordance with my present invention, the cover being removed. Fig. 2 is a longitudinal sectional view through the device, and Fig. 3 is a perspective view of the movable contact and lever therefor.

Referring now to the accompanying drawing in detail, the numeral 1 designates a base board constructed of any suitable material and formed adjacent to one end with an arcuate shaped slot 2 and adjacent to the opposite end with a similar relatively short slot 3 curved in a direction reverse to that of the slot 2. Fulcrumed upon the under side of the base board 1 at the center of the arc of the slot 2 is a lever 4 having the free end of the long arm thereof terminat ing below the slot 2 and equipped with an outwardly extending pin 5 projecting through the slot 2 and having the upper end thereof threaded as at 6 and of noncircular contour to receive one end of an indicator finger 7 movable over a scale 8 formed on the base 1. The free end of the short arm of the lever terminates immediately below the short slot 3 and has formed integral therewith an upwardly projecting finger 9 twisted upon itself as at 10 and carrying at its upper end a contact 11 extending above the upper surface of the base board 1. In a plane below and to one side of the contact 11 is a bracket 12 to which is secured one extremity of a Specification of Letters Patent.

Patented Apr. 7, 1914.

Serial No. 772,326.

curved thermostatic element 13 composed, in the present instance, of strips of steel and brass 14 and 15 respectively suitably fastenedtogether, the free end of such element carrying a contact 16 adapted to engage the contact 11.

The numerals 17, 17 designate binding posts secured upon the base 1 and from one of such posts leads a conductor 18 terminally connectedto the bracket 12 while from the remaining post leads a conductor 19 terminally connected to a plate 20 contactmg with the lever 4 at the fulcrum of the latter.

From the foregoing description taken in connection with the accompanying drawing, the construction, mode of operation and manner of employing my invention will be readily apparent.

Inpractice, the terminals of the electric circuit are connected to the binding posts 17, 17 and the lever 4 swung about its fulcrum to the desired position, determined by the finger 7 and the scale 8 whereby the device may be set to operate at any predetermined temperature. After the proper adjustment has been obtained, the manipulating nut 21 threadedly engaging the threaded end of the pin 5 is tightened whereby the indicating finger frictionally engages the adjacent part of the base board to hold the lever against accidental movement. In the movement of the lever, the contact 11 is adjusted relatively to the contact carried by the thermostatic element and owing to the twisted portion of the finger 9 such contact 11 is disposed in a path to nicely receive the contact 16 when the latter is moved under the action of the thermostatic element. After the device has been set and the surrounding atmosphere reaches the predetermined degree, the thermostatic element expands and so closes the circuit at the contacts 16 and 11, as is readily apparent.

It will be seen that I have provided a thermostatic circuit closer which may be readily installed in an electric circuit and which may be set to close the circuit at any predetermined temperature.

The thermostatic element of the contacts is preferably incased by means of a cover 22 mounted upon the base board 1 and suitably secured thereto.

I claim:

A thermostatic circuit closer comprising a base board having an arcuate-shaped slot formed adjacent to one end thereof and a similar relatively short slot formed adjacent to the opposite end and curved in a direction opposite to that of the first slot and struck on an are having the same center as that of the first slot, a lever fulcrumed at the center of said arcs, a finger carried by one end of said lever and projecting through said short slot and twisted upon itself, forming a contact, a bracket secured to the base at one side of said contact, a thermostatic element having one end fastened to said bracket and its opposite end disposed in proximity to said contact, a second contact carried by the lastmentioned end of said thermostatic elementand adapted to engage said first contact, a

pin carried by the opposite end of said lever and projecting through the first-mentioned slot and an indicator finger carried by said pin and movable over a scale formed on said base board adjacent to said first slot and a nut threaded onto said pin and adapted to bind against the adjacent face of said base to prevent accidental movement of the lever subsequent to the adjustment. thereof.

In testimony whereof I affiX my signature in presence of two Witnesses.

ROBERT L. SHANNON.

Witnesses E. P. JOHNSON, A. M. RICHARDSON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

